According to a known electric wire, an end portion of an electric wire (a joint conductor) which end portion extends over a predetermined range from a tip of the wire is plastically deformed so that a sectional area thereof becomes smaller than that of a main portion of the conductor, and the wire is constructed so that the main portion and a part of the end portion near the main portion are coated uniformly with an insulating film, then two such electric wires (joint conductors) are joined together in a matched state of respective end portions.
[Patent Literature 1]
Japanese Patent Laid-Open Publication No. 2002-95198
In the above conventional technique, since the sectional area of the end portion is decreased while preventing damage of the insulating film, a heat input quantity can be decreased. Consequently, there is no fear that an insulating material located near a joined portion may be deteriorated with heat produced a joining work, and hence the insulating performance is not impaired.
In the above conventional technique, however, if two electric wires (joint conductors) are positioned adjacent each other in a peeled state of respective insulating coatings, there is formed a gap with corresponding to the total thickness of both conductor's insulating coatings as skin layers in a joined face portion between end portions of the conductors. The gap becomes larger because the conductors are tapered at their tips. Therefore, the adhesion between both conductors is impaired, with a consequent fear of occurrence of joining imperfection.
It is an object of the present invention to minimize the gap developed between electric wires (joint conductors), thereby improving the reliability of joining, and facilitate the conductor joining work, thereby improving the productivity of a state of a rotary electric machine such as, for example, an AC generator for a vehicle.